Compare 15/21 and 9/40
15/21 is greater than 9/40
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
15/21 = 15 × 40/21 × 40 = 600/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
9/40 = 9 × 21/40 × 21 = 189/840 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 600/840 > 189/840 or 15/21 > 9/40
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